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Date: Mon, 17 Apr 2006 15:02:38 -0700
From: Ravikiran G Thirumalai <kiran@scalex86.org>
To: Christoph Lameter <clameter@sgi.com>
Cc: Nick Piggin <nickpiggin@yahoo.com.au>,
       Steven Rostedt <rostedt@goodmis.org>,
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Subject: Re: [PATCH 00/05] robust per_cpu allocation for modules
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On Mon, Apr 17, 2006 at 09:55:02AM -0700, Christoph Lameter wrote:
> On Sat, 15 Apr 2006, Nick Piggin wrote:
> 
> > If I'm following you correctly, this adds another dependent load
> > to a per-CPU data access, and from memory that isn't node-affine.
> 
> I am also concerned about that. Kiran has a patch to avoid allocpercpu
> having to go through one level of indirection that I guess would no 
> longer work with this scheme.

The alloc_percpu reimplementation would work regardless of changes to
static per-cpu areas.  But, any extra indirection as was proposed initially
is bad IMHO. 

>  
> > If so, I think people with SMP and NUMA kernels would care more
> > about performance and scalability than the few k of memory this
> > saves.
> 
> Right.

Me too :)

Kiran